Abstract
Ranking countries via index-based league tables is now commonplace and is said by its proponents to provide countries with an ability to compare performance with their peers, spurring them to learn from others and make improvements. The Human Development Index (HDI) is arguably one of the most influential indices of its type in terms of reporting within the media and influence on development policy and funding allocation. It is often used as part of a suite of indices to assess sustainability. The index was first published in the Human Development Report (HDR) of 1990 and has appeared in each of the HDRs published since then. This paper reports the first research of its type designed to explore the impacts of methodological changes over 28 years (1991 to 2018) on the ranks of a sample of 135 countries appearing in the HDRs. Results suggest that methodological changes in the HDI have had a statistically significant impact on the ranking of the majority (82%) of countries in the sample, and the ranks of countries that tend to appear towards the top, middle, or bottom of the HDI league table are just as likely to be influenced by changes in HDI methodology. The paper suggests that after nearly 30 years of the HDI, there is an urgent need for independent and empirical research on the changes that it has helped bring about.